Theoretical and Numerical Analysis of Anterior Cruciate Ligament Injury and its Prevention

Abstract

Anterior cruciate ligament (ACL) injury is one of major risks for most athletes. ACL injury can be caused by many risk factors such as anatomic risk factors, biomechanical risk factors and environmental risk factors. In this article, numerical and theoretical analysis is conducted to investigate biomechanical risk factors. An entire threedimensional finite element knee model is built based on MRI data. Anterior Tibial Translations (ATT) at different knee flexion angles are simulated by finite element models. In the simulations, more attention is given to material properties of different knee components and their effects on ACL injury. Mechanical response of ACL during sport activities is highly determined by its viscoelastic properties. Unfortunately, viscoelastic properties of two bundles of ACL will change dramatically even with several hours' physical aging. As a consequence, ACL will experience mechanical ductile to brittle transition due to daily physical aging. Theory of physical aging from polymer science is, for the first time, introduced to understand ACL injury and its prevention. By analogy to physical aging of amorphous polymer materials, we think physical aging of two bundles of ACL will largely increase risk of ACL injury. Besides, physical aging will also build a heterogeneous stress and strain in ACL due to its natural anatomic structure, which is a large risk for athletes. The specific designed prevention programs for ACL injury such as plyometrics, strengthening and other neuromuscular training exercises [1] are believed to erase physical aging of ACL. ACL with less physical aging is less likely to get injured in sport activities. In this article, a virtual physical aging simulation is built to validate current hypothesis. Erasing physical aging of ACL may provide an accurate and quantitative way to prevent ACL injury.lobal Journal of Researches in Engineering ( ) Volume Xx X Issue I Ve rsion I 43Year 2020 J Gl risks for most athletes. ACL injury can be caused by many risk factors such as anatomic risk factors, biomechanical risk factors and environmental risk factors. In this article, numerical and theoretical analysis is conducted to investigate biomechanical risk factors. An entire three-dimensional finite element knee model is built based on MRI data. Anterior Tibial Translations (ATT) at different knee flexion angles are simulated by finite element models. In the simulations, more attention is given to material properties of different knee components and their effects on ACL injury. Mechanical response of ACL during sport activities is highly determined by its viscoelastic properties. Unfortunately, viscoelastic properties of two bundles of ACL will change dramatically even with several hours' physical aging. As a consequence, ACL will experience mechanical ductile to brittle transition due to daily physical aging. Theory of physical aging from polymer science is, for the first time, introduced to understand ACL injury and its prevention. By analogy to physical aging of amorphous polymer ma...

Digest Ultrasonic Welding I: Localized Heating and Fuse Bonding

“…How this mechanical energy changes to thermal energy is what we will discuss below. Currently most researchers explained this transition from mechanical energy to thermal energy by using linear viscoelastic theory [39,40]. Loss modulus is used to calculate the thermal energy.…”

Simulation of Wave in Hypo-Elastic-Plastic Solids Modeled by Eulerian Conservation Laws

“…In order to investigate shear band propagation, Eremin et al [30] used microstructure based finite-difference method to model plastic flow in low carbon steel. Heuze and Stainier [31] created a variational framework which will let hyperbolic conservation laws work with thermo-hyperelastic-viscoplastic constitutive equations [32]. Aided with a high-order and pressure oscillating-free scheme, Eulerian description of conservation laws as well as a hyper-elastic framework were also used to understanding multi-material elastic-plastic flow [33,34].…”